It is one of several peace encyclicals of Pope Pius XII focusing in particular on the dangers to peace during the Holy Year. It was given at Rome, at St. Peter's on July 19, 1950, the twelfth day of his Pontificate.

Author: Pope Pius XII | Source: http://www.papalencyclicals.net

SUMMI MAERORIS

ENCYCLICAL OF POPE PIUS XII ON PUBLIC PRAYERS FOR PEACE JULY 19, 1950

To the Patriarchs, Primates, Archbishops, Bishops, and other Ordinaries in Peace and Communion with the Apostolic See.

Assuredly We have reasons to be moved with the deepest sorrow and at the same time with the greatest joy. On the one hand, We behold the spectacle of countless multitudes who are coming to Rome from every country of the world during this Year of Jubilee, and who are giving here an outstanding testimony of oneness in faith, of brotherly unity, of an ardent piety, in such numbers as this Beloved City, which in the course of centuries has witnessed so many celebrated events, has never before seen until now. With loving solicitude, We welcome these multitudes beyond number, consoling them with paternal exhortations, and, setting before them new and resplendent examples of holiness, We call them back, with the fruitful effect, to the path of renewed virtue and Christian living.
2. On the other hand, as We behold the present social conditions of the people, they are such as to give us reason for the keenest anxiety and concern. Though many are discoursing, writing and speaking on the method needed to arrive finally at the peace that is so much desired, some have neglected or openly repudiated the principles that must constitute its solid foundation. Indeed, in not a few countries, falsehood instead of truth has been presented under a certain guise of reasonableness; not love, not charity have been fostered, but hatred and a blind rivalry are being encouraged; not concord among citizens is exalted, but disturbance and disorder are being provoked.
3. However, as sincere and thoughtful persons recognize, it is not in this way that either the problems which still separate nations can be solved, or the proletariat classes be guided, as they should, towards a better future. Never, be it said, has hatred or Iying or disorder generated any good. Unquestionably, people who are needy should be raised to a status that is worthy of man; yet not with force, not with violence, but with laws that are just. What must certainly be done, under the auspices of truth and the guidance of justice, is to eliminate as soon as possible all the differences which separate and divide peoples.
4. As the heavens are becoming darkened by heavy clouds, We, who have dearest at heart the liberty, dignity and prosperity of all nations, must need return to exhorting earnestly all citizens and their governments to a true concord and peace.
5. Let all of them remember what war brings in its wake, as we know only too well from experience -- nothing but ruin, death and every sort of misery. With the progress of time, technology has introduced and prepared such murderous and inhuman weapons as can destroy not only armies and fleets, not only cities, towns and villages, not only the treasurers of religion, of art and culture, but also innocent children with their mothers, those who are sick and the helpless aged.
6. Whatever the genius of man has produced that is beautiful and good and holy, all of this can be practically annihilated. But if a war, especially today, appears to every honest observer as something terrifying and deadly, there is yet reason to hope -- through the efforts of all people and particularly of their rulers -- that the dark and menacing clouds which presently cause such trepidation may pass away, and that true peace may finally reign among nations.
7. However, realizing that "every best gift and every perfect gift is from above, coming down from the Father of lights" (James 1, 17), We consider it opportune, Venerable Brothers, to call once again for public prayers and supplications to implore concord among peoples.
8. It will be the care of your pastoral zeal not only to urge the souls committed to you to raise fervent prayers to God, but also to encourage them to works of penance and expiation, by which the Divine Majesty, which has been offended by so many grievous public and private crimes, can be appeased.
9. Meanwhile, in accordance with your office, give notice to the faithful of this our paternal invitation; recall to them once more from what principles a just and lasting peace may issue and by what means it must be sought. Indeed, as you well know, it can only be obtained from the principles and norms dictated by Christ and put into practice with sincere piety. Such principles and norms, in fact, recall men to truth, justice and charity; they put a restraint on their unruly desires; they force the senses to be obedient to reason; they move the reason to obey God; they produce this effect, that all men, even those who are rulers of the peoples, may recognize the freedom that is due to religion, which, beyond its primary purpose of leading souls to eternal salvation, has also another, of safeguarding and protecting the very foundations of the State.
10. From what We have said so far, it is easy to conclude, Venerable Brothers, how far removed from procuring a secure peace are those who trample under foot the sacred rights of the Catholic Church. They forbid her ministers the free exercise of religious worship. They even condemn them to exile and to prison. They impede or directly proscribe and destroy schools and institutes of education which are conducted according to Christian norms and principles. Through errors, calumnies and every kind of indecency, they draw the people, especially the tender youth, away from integrity of morals, from virtue and innocence, to the allurements of vice and corruption.
11. It is also clear of what error they are guilty who insidiously launch the charge against this Apostolic See and the Catholic Church of desiring another conflagration.
12. As a matter of fact, there have never been lacking, either in ancient or in more recent times, those who tried to subjugate the peoples by the use of arms; on the other hand, We have never ceased to promote a true peace. The Church desires to win over peoples and to educate them to virtue and right social living, not by means of arms but with the truth. For "the weapons of our warfare are not carnal, but mighty to God" (II Cor. 10, 4).
13. You must teach all this with frankness; because only when the Christian commandments inform private and public life, only then may we rightly hope that, after human dissensions have been composed, the various classes of citizens, peoples and nations will live together in brotherly concord.
14. May the new supplication implore of God the fulfillment of these our ardent desires; in such wise that, with the help of Divine grace, the morals of all men may be renewed by Christian virtue, and the relations between peoples may, as soon as possible, be so ordered that, after the blind ambition to dominate others has been put in check, in every nation there may obtain the necessary liberty which is due, according to Divine and human rights, to the Church and all her sons.
15. With this confidence, We impart, from our heart, the Apostolic Benediction, as a pledge of Divine graces and of our paternal affection, to all of you, Venerable Brothers, to your clergy and faithful, and to all those who in a special manner correspond with these our exhortations.

Given at Rome, at St. Peter's July 19, 1950, the twelfth of our Pontificate.